Using the login and user you provided to me, I succeeded to make your WordPress host connect to your Joomla database. Now you don’t have the “Access denied for user” message anymore.
But the plugin doesn’t import anything. It is because your Joomla version is 1.0. My plugin is only compatible with Joomla 1.5.

Sorry, it worked, wicked!
In fact I was on a different host. Once I’ve moved on the same host everything went fine.
Your plugin worked perfectly: text, formatting and pictures.
It’s a little gem, well done and thank you.